1. Field of the Invention
This invention relates to a circuit substrate device, on which a pattern conductor has been formed properly, a method for producing the same, a semiconductor device, and a method for producing the same. This application claims priority of Japanese Patent Application No.2002-105549, filed on, 2002, the entirety of which is incorporated by reference herein.
2. Description of Related Art
Recently, there is raised a demand for a technique of mounting functional elements, such as semiconductor chips, on e.g., a substrate, to a high density, for keeping up to the reduction in size and thickness, and to the advanced and diversified functions of electronic equipment. These functional elements are mounted on the substrate in the form of a mold package, such as QFP (Quad Flat Package) or a SOP (Small Outline Package), a package of a smaller size, such as BGA (Ball Grid Array) or CSP (Chip Scale Package), or MCM (multi-chip module), for mounting plural semiconductor chips.
In the mounting configuration for the functional elements, such as BGA, CSP or MCM, a semiconductor chip is mounted on a wiring substrate by pair-chip mounting, and an electrode land is arranged on a surface of the wiring substrate opposite to the surface thereof mounting the wiring substrate. The electrode land is used as a connection terminal to a motherboard.
As a substrate for mounting the semiconductor chip, a wiring substrate of an organic material, such as a glass epoxy substrate or a polyimide substrate, or a wiring substrate of an inorganic material, such as ceramics substrate. In particular, as the wiring substrate of an organic material, used for mounting a semiconductor chip having a large number of connecting terminals, such as connection pins, or used for MCM mounting, a multi-layer wiring substrate 100, or a so-called FR (flame-retardant) substrate, is used, as shown in FIG. 1. This multi-layer wiring substrate 100 includes a via-hole 102, with a diameter on the order of 50 xcexcm, for interconnecting multi-layered pattern conductors 101 by for example laser processing. With this multi-layer wiring substrate 100, the line width of the pattern conductor 101 can be as fine as approximately 100 xcexcm.
However, with the above-described multi-layer wiring substrate 100, there is raised, in keeping up with the tendency towards an increased number of the semiconductor chips and a decreased pitch between the connection pins, a demand for increasing the density of the pattern conductors 101 on the surface of the multi-layered pattern conductors 101 mounting the semiconductor chip. Since the number of the lines in the semiconductor chip for MCM mounting in near future amounts to several thousands or to several tens of thousands, it is required to raise the density of the pattern conductors 101 further.
If, in the present multi-layer wiring substrate 100, plural semiconductor chips are connected to a large number of conductor patterns, it becomes necessary to increase the mounting area or to increase the number of layers of the pattern conductors 101. With the multi-layer wiring substrate 100, the line length of the pattern conductors 101 in increased, while the number of the via-holes 102 is increased with increasing numbers of the via-holes, with the consequence that the numbers of the C, L and R components in the pattern conductors 101 may be increased to deteriorate electrical characteristics.
Moreover, in producing the multi-layer wiring substrate 100, the manufacturing process may be complex with the increasing number of the layers of the pattern conductors 101 to increase the production time or to lower the production efficiency.
On the other hand, a wiring substrate of an inorganic material, such as Si substrates or glass substrates, may also be used in place of the multi-layer wiring substrate 100. Since these Si or glass substrates are superior in surface smoothness and in thermal resistance, pattern conductors may be formed on its mounting surface for semiconductor chips, by employing for example the thin film forming technique, to a finer line width than is possible with the above-described multi-layer wiring substrate 100.
However, with the Si substrate or the glass substrate, it is difficult to form e.g., via-holes, such that electrode lands, operating as connection terminals for a motherboard, cannot be formed on a surface on the opposite side of the mounting surface for the semiconductor chip, with the consequence that these substrates cannot be used as mounting substrates for the semiconductor chips.
It is therefore an object of the present invention to provide a circuit substrate device and a semiconductor device superior in electrical properties and in high frequency characteristics and which may prohibit the production time and production cost from being increased while prohibiting the production efficiency from being lowered. It is another object of the present invention to provide a method for producing the circuit substrate device and a method for producing a semiconductor device.
In one aspect, the present invention provides a circuit substrate device including a circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), the land unit connecting to the pattern conductor, and a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof. The circuit unit is formed through a release layer on a dummy substrate, having a flattened out surface, while the circuit unit is connected to the major surface of the multi-layer wiring substrate so that the land unit is connected to the connecting portion. The dummy substrate and the release layer are removed by peeling at the release layer to give a structure comprised of the circuit unit formed on the major surface of the multi-layer wiring substrate.
This circuit substrate device is formed by forming a circuit unit on a dummy substrate with a planar surface, with the interposition of a release layer, and by peeling off the dummy substrate and the release layer after the circuit unit having a pattern conductor is attached to the major surface of the multi-layer wiring substrate. With this circuit substrate device, since the waprin or the inundations of the circuit unit along the direction fo thickness may be suppressed, the circuit unit having the fine pattern conductor formed to high accuracy may be formed on the the major surface of the multi-layer wiring substrate.
In still another aspect, the present invention provides a method for producing a circuit substrate device comprising a circuit unit forming step of forming a circuit unit through a release layer, with the circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), connecting to the pattern conductor, a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof, a bonding step of connecting the circuit unit to the major surface of the multi-layer wiring substrate for connecting the land unit to the connecting portion, and a removing step of removing the dummy substrate and the release layer by releasing the release layer from the circuit unit.
In this method for producing a circuit substrate device, the circuit substrate device is formed by forming a circuit unit on a dummy substrate with a planar surface, with the interposition of a release layer, and by peeling off the dummy substrate and the release layer after the circuit unit having a pattern conductor is attached to the major surface of the multi-layer wiring substrate. With this circuit substrate device, since the warping or the inundations of the circuit unit along the direction fo thickness may be suppressed, the circuit unit having the fine pattern conductor formed to high accuracy may be formed on the major surface of the multi-layer wiring substrate.
In still another aspect, the present invention provides a method for producing a circuit substrate device comprising a circuit set forming step of forming a set of circuits, composed of a plurality of circuit units arrayed side by side, via a release layer, each circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), connecting to the pattern conductor, an inspecting step of subjecting the set of circuits to preset inspection as to whether or not the pattern conductor has been properly formed, from one circuit unit to another, a splitting step of splitting the dummy substrate and the set of circuits, as the set of circuits has been formed on the dummy substrate, from one circuit unit to another, a sorting step of accepting only the circuit unit the pattern conductor of which has been found in the inspecting step to have been formed properly, a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof, a bonding step of bonding the circuit unit, accepted in the inspecting step, to the major surface of the multi-layer wiring substrate so that the land unit is bonded to the major surface of the multi-layer wiring substrate, and a removing step of removing the dummy substrate and the release layer by peeling at the release layer from the circuit unit.
With this method for producing a circuit substrate device, it is checked in the inspecting step whether or not the pattern conductor is properly formed, from one circuit unit of the circuit set to another, and only the circuit unit the pattern conductor of which has been formed properly is selected in the sorting step, so that only the circuit unit which is not defective may be connected to the multi-layer wiring substrate, thus improving the production efficiency.
Moreover, since the dummy substrate is removed after bonding the circuit unit to the multi-layer wiring substrate, a circuit substrate device may be produced which has a fine pattern conductor of a high accuracy freed of warping or inundations in the direction of thickness on the major surface of the multi-layer wiring substrate.
In still another aspect, the present invention provides a method for producing a circuit substrate device comprising a circuit set forming step of forming a set of circuits, comprised of a plurality of circuit units arrayed side by side, through a release layer, each circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), connecting to the pattern conductor, a substrate set forming step of forming a set of a plurality of multi-layer wiring substrates arrayed side by side in a facing relationship to the circuit units of the circuit set, each multi-layer wiring substrate including a connecting portion exposed from the major surface thereof, a bonding step of bonding the circuit set to the substrate set so that the land unit of the circuit unit is connected to the connecting portion of the multi-layer wiring substrate lying in a facing relationship to the land unit, a removing step removing the dummy substrate and the release layer by peeling the release layer from the circuit set, and a splitting step of splitting the circuit set and the substrate set in a lump, as the circuit set and the substrate set are bonded to each other, from one circuit unit to another.
With this method for producing a circuit substrate device, the circuit set and the substrate set are bonded together in the bonding step, and the dummy substrate is removed in the removing step, after which the resulting assembly is split in the splitting step, on the circuit unit basis, with the circuit set and the substrate set remaining attached to each other. Thus, plural circuit substrate devices may be produced in a lump thus improving the production efficiency and decreasing the time needed in production.
Moreover, in this method for producing a circuit substrate device, in which the dummy substrate is removed after bonding the circuit set to the substrate set, a circuit substrate device may be produced which has a fine pattern conductor of a high accuracy freed of warping or inundations in the direction of thickness on the major surface of the multi-layer wiring substrate.
In still another aspect, the present invention provides a method for producing a circuit substrate device comprising a circuit set forming step of forming a set of circuits, comprised of a plurality of circuit units arrayed side by side, via a release layer, each circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), for connecting to the pattern conductor, an inspecting step of subjecting the set of circuits to preset inspection as to whether or not the pattern conductor has been properly formed, from one circuit unit to another, a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof, a bonding step of bonding the multi-layer wiring substrate only to the circuit unit, the pattern conductor of which has been found in the inspecting step to have been formed properly, so that the land unit is connected to the connecting portion, a removing step of removing the dummy substrate and the release layer so that the release layer is peeled from the circuit set, and a splitting step of splitting the circuit set into the circuit units as the multi-layer wiring substrate is attached thereto.
With the present method for producing a circuit substrate device, it is checked in the inspection step whether or not the pattern conductor has been properly formed, from one circuit unit of the circuit set to another, the multi-layer wiring substrate is bonded in the bonding step only to the circuit unit(s) of the circuit set, the pattern conductor of which has been formed properly, the dummy substrate is removed in the removing step and subsequently the resulting circuit substrate device is split in the splitting step, as the circuit set and the substrate set are bonded together, on the circuit unit basis. Thus, a plural number of the circuit substrate devices, comprised of the satisfactory circuit units and the multi-layer wiring substrates, bonded thereto, may be prepared in a lump, thereby appreciably improving the production efficiency and decreasing the production time.
Moreover, with the present method for producing a circuit substrate device, since the dummy substrate is removed after bonding the circuit set to the multi-layer wiring substrate, a circuit substrate device may be produced having a circuit unit formed on the major surface of the multi-layer wiring substrate having a pattern conductor formed on its major surface to a fine line width and high accuracy in a manner free of warping or inundations in the direction of thickness.
In still another aspect, the present invention provides a semiconductor device comprising a circuit substrate unit including a circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), connecting to the pattern conductor, with the circuit substrate also including a multi-layer wiring substrate, including in turn a connecting portion exposed from a major surface thereof, and a semiconductor chip mounted on the circuit substrate unit by being electrically connected to the pattern conductor. The circuit substrate unit is so formed that the circuit unit is formed via a release layer on a dummy substrate, having a flattened out surface. The circuit unit is bonded to the major surface of the multi-layer wiring substrate so that the land unit is connected to the connecting portion, the dummy substrate and the release layer being then removed by peeling at the release layer to form the circuit unit on the major surface of the multi-layer wiring substrate.
In this semiconductor device, the circuit unit is formed on the dummy substrate, having a flattened out surface, with the interposition of a release layer, and a circuit unit, having a pattern conductor by a thin film technique, bonded to the major surface of the multi-layer wiring substrate, after which the dummy substrate and the release layer are removed to form the circuit substrate unit. Thus, with the present semiconductor device, since the warping or inundations along the thickness of the circuit unit in the circuit wiring substrate may be suppressed, the circuit unit having a pattern conductor of a fine line width may be formed to high accuracy on the major surface of the multi-layer wiring substrate.
In still another aspect, the present invention provides a method for producing a semiconductor device comprising a circuit substrate unit forming step of forming a circuit substrate unit by a circuit unit forming step of forming a circuit unit through a release layer, with the circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), connecting to the pattern conductor, a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof, a bonding step of bonding the circuit unit to the major surface of the multi-layer wiring substrate for connecting the land unit to the connecting portion, and a removing step of removing the dummy substrate and the release layer by releasing the release layer from the circuit unit, and a mounting step of electrically connecting the pattern conductor to a semiconductor chip for mounting the semiconductor chip.
With the present method for producing a semiconductor device, the circuit unit is formed on the dummy substrate, having a flattened out surface, with the interposition of a release layer and, after bonding the circuit unlit, having the pattern conductor by a thin film technique, to the major surface of the multi-layer wiring substrate, the dummy substrate and the release layer are removed to form the circuit substrate unit. Thus, with the present method for producing the semiconductor device, such a semiconductor device may be produced including a circuit substrate unit having a circuit unit on the major surface of the multi-layer wiring substrate, with the pattern conductor being free from warping or inundations along the thickness and being formed to fine line width and to high accuracy.
In still another aspect, the present invention provides a method for producing a semiconductor device comprising a circuit substrate forming step of forming circuit substrate by circuit set forming step of forming a set of circuits, comprised of a plurality of circuit units arrayed side by side, via a release layer, each circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layer(s), connecting to the pattern conductor, an inspecting step of subjecting the set of circuits to preset inspection as to whether or not the pattern conductor has been properly formed, from one circuit unit to another, a splitting step of splitting the dummy substrate and the set of circuits, as the set of circuits has been formed on the dummy substrate, from the circuit unit to another, a sorting step of accepting only the circuit set the pattern conductor of which has been found in the inspecting step to have been formed properly, a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof, a bonding step of bonding the circuit unit, accepted in the inspecting step, to the major surface of the multi-layer wiring substrate so that the land unit is bonded to the connecting portion, and a removing step removing the dummy substrate and the release layer by peeling at the release layer, and a mounting step of mounting the semiconductor chip on the circuit substrate by electrically connecting the pattern conductor to the semiconductor chip.
With the present method for producing this semiconductor device, it is checked in the circuit substrate forming step whether or not the pattern conductor has been formed properly, from one circuit unit of the circuit set to another, and only the circuit unit, the pattern conductor of which has been formed properly, is accepted in the sorting step, such a circuit substrate unit, composed of the multi-layer wiring substrate bonded to only a satisfactory circuit unit, is produced, thus improving the production efficiency.
Moreover, with the present method for producing this semiconductor device, the dummy substrate is removed after bonding the circuit unit to the multi-layer wiring substrate, in the circuit substrate forming step, such a semiconductor device may be produced including a circuit substrate unit having a circuit unit on the major surface of the multi-layer wiring substrate, with the pattern conductor being free from warping or inundations along the thickness and being formed to fine line width and to high accuracy.
In still another aspect, the present invention provides a method for producing a semiconductor device comprising a circuit substrate forming step of forming a set of circuits, comprised of a plurality of circuit units arrayed side by side, via a release layer, each circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layers, connecting to the pattern conductor, a substrate set forming step of forming a set of a plurality of multi-layer wiring substrates arrayed side by side in a facing relationship to the circuit units of the circuit set, with each multi-layer wiring substrate including a connecting portion exposed from the major surface thereof, a bonding step of bonding the circuit set to the substrate set so that the land unit of the circuit unit is connected to the connecting portion of the multi-layer wiring substrate lying in a facing relationship to the land unit, a removing step removing the dummy substrate and the release layer by peeling at the release layer, and a splitting step of splitting the circuit set and siad substrate set in a lump from one circuit unit to another, and a mounting step of mounting the semiconductor chip on the circuit substrate by electrically connecting the pattern conductor to the semiconductor chip.
With the present method for producing the semiconductor device, the circuit set and the substrate set are bonded together in the bonding step in the circuit substrate unit forming step in a lump, and the dummy substrate is removed in the removing step, after which the circuit substrate unit is split in the splitting step on the circuit unit basis, with the circuit set and the substrate set remaining bonded to each other, so that a plural number of the circuit substrate units may be produced in a lump, thus improving the production efficiency and decreasing the production time.
Moreover, with the present method for producing the semiconductor device, since the dummy substrate is removed after bonding the circuit unit to the substrate unit, such a semiconductor device may be produced including a circuit substrate unit having a circuit unit on the major surface of the multi-layer wiring substrate, with the pattern conductor being free from warping or inundations along the thickness and being formed to fine line width and to high accuracy.
In yet another aspect, the present invention provides a method for producing a semiconductor device comprising a circuit substrate forming step of forming a set of circuits, comprised of a plurality of circuit units arrayed side by side, via a release layer, each circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, with the circuit unit also having a land unit, on an uppermost layer of the wiring layers, connecting to the pattern conductor, an inspecting step of subjecting the set of circuits to preset inspection as to whether or not the pattern conductor has been properly formed, from one circuit unit to another, a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from the major surface, a bonding step of bonding the multi-layer wiring substrate only to the circuit unit the pattern conductor of which has been found in the inspection step to have been formed properly, so that the land is connected to the connecting portion, a removing step of removing the dummy substrate and the release layer by peeling the release layer from the circuit set, and a splitting step of splitting the set of circuits, as the set of circuits has been bonded to the multi-layer wiring substrate, into the circuit units, and a mounting step of mounting the semiconductor chip on the circuit substrate by electrically connecting the pattern conductor to the semiconductor chip.
With the present method for producing a semiconductor device, it is checked in the inspection step, whether or not the pattern conductor has been formed properly, from one circuit unit of the circuit set to another, and the multi-layer wiring substrate is bonded in the bonding step only to the circuit unit of the circuit set where the pattern conductor has been formed properly. After the dummy substrate has been removed in the removing step, the resulting circuit substrate set is split in the splitting step, on the circuit unit basis, with the circuit set remaining attached to the multi-layer wiring substrate, whereby a plural number of the circuit substrates, each composed of the multi-layer wiring substrate bonded to the satisfactory circuit unit, may be produced in a lump, thus improving the production efficiency and decreasing the production time appreciably.
Additionally, with the present method for producing a semiconductor device, in which the dummy substrate is removed after bonding the multi-layer wiring substrate to the circuit set, such a semiconductor device may be produced including a circuit substrate unit having a circuit unit on the major surface of the multi-layer wiring substrate, with the pattern conductor being free from warping or inundations along the thickness and being formed to fine line width and to high accuracy. With the present invention, a circuit unit is formed via a release layer on a dummy substrate, having a flattened out surface, with the dummy substrate and the release layer being removed after bonding the circuit unit having the pattern conductor by the thin film technique is bonded to the multi-layer wiring substrate. As a result, the circuit substrate device and the semiconductor device, suppressed in warping and inundations along the thickness of the circuit unit, may be produced.
Thus, according to the present invention, the circuit unit, including a pattern conductor, as a fine line formed to a high density and a high accuracy, may be formed on the multi-layer wiring substrate, so that a circuit substrate device, improved in electrical characteristics and reduced in size, and a semiconductor device, having a semiconductor chip mounted on this circuit substrate device, may be produced.
Moreover, according to the present invention, the circuit unit, found to be defective as to the pattern conductor in the inspection step, may be prohibited from being bonded to the multi-layer wiring substrate, so that it is possible to improve the production efficiency and to lower the cost in producing the circuit substrate device or the semiconductor device. Additionally, since plural circuit substrate devices can be formed in a lump by employing the circuit set or the substrate set, it is also possible to decrease the production time and to improve the production efficiency in producing the circuit substrate device or the semiconductor device. Since the dummy substrate can be re-used, it is possible to decrease the cost further cost in producing the circuit substrate device or the semiconductor device.